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<table width="100%" summary="page for algae"><tr><td>algae</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Volume of algae as function of increasing concentrations of a herbicide</h2>

<h3>Description</h3>

<p>Dataset from an experiment exploring the effect of increasing concentrations of a herbicide on 
the volume of the treated algae.
</p>


<h3>Usage</h3>

<pre>data(algae)</pre>


<h3>Format</h3>

<p>A data frame with 14 observations on the following 2 variables.
</p>

<dl>
<dt><code>conc</code></dt><dd><p>a numeric vector of concentrations.</p>
</dd>
<dt><code>vol</code></dt><dd><p>a numeric vector of response values, that is relative change in volume.</p>
</dd>
</dl>



<h3>Details</h3>

<p>This datasets requires a cubic root transformation in order to stabilise the variance.
</p>


<h3>Source</h3>

<p>Meister, R. and van den Brink, P. (2000)
<em>The Analysis of Laboratory Toxicity Experiments</em>,  
Chapter 4 in <em>Statistics in Ecotoxicology</em>, Editor: T. Sparks, 
New York: John Wiley \&amp; Sons, (pp. 114&ndash;116). 
</p>


<h3>Examples</h3>

<pre>

algae.m1 &lt;- drm(vol~conc, data=algae, fct=LL.3())
summary(algae.m1)

algae.m2 &lt;- boxcox(algae.m1)
summary(algae.m2)

</pre>


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